Materials Data on SrB4O7 by Materials Project

SrB4O7 crystallizes in the orthorhombic Pmn2_1 space group. The structure is three-dimensional. Sr2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Sr–O bond distances ranging from 2.56–2.88 Å. There are two inequivalent B3+ sites. In the first B3+ site, B3+ is bonded to four O2- atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.43–1.57 Å. In the second B3+ site, B3+ is bonded to four O2- atoms to form corner-sharing BO4 tetrahedra. There is three shorter (1.46 Å) and one longer (1.57 Å) B–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent Sr2+ and two B3+ atoms. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to two equivalent Sr2+ and two B3+ atoms. In the third O2- site, O2- is bonded in a trigonal planar geometry to three B3+ atoms. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Sr2+ and two equivalent B3+ atoms.